diff --git a/class/core/public.py b/class/core/public.py
index 1e518e865..96eafa2e4 100755
--- a/class/core/public.py
+++ b/class/core/public.py
@@ -809,7 +809,7 @@ def toSize(size):
     for b in d:
         if size < 1024:
             return str(round(size, 2)) + ' ' + b
-        size = size / 1024.0
+        size = float(size) / 1024.0
         s = b
     return str(round(size, 2)) + ' ' + b